I just finished work on yet another coffee table design- probably my last one for the time being. With this post I want to go a little farther than usual and show the actual step-by-step process that goes into creating one of my pieces.
A few weeks ago when I wrote about my 4-Piece Study (check out the previous post), I realized that the design had a lot of potential to be something more than just a small sculpture. I thought for a little while about what the form was well-suited for and decided that, although I have already made several different coffee tables, this design was too good to not make another one. While I usually start my process with lots of sketching, this time I already had a 3d prototype. I just had to make it bigger.
Lamination is a means of forming curved pieces of wood and it is one of the two main processes I used in creating the prototype and subsequent coffee table. There are three main steps in laminating a piece of wood. First, you need to cut out thin, bendable strips of wood, about 1/8" thick. This step is most easily done on a table saw. For this project, I started with two boards of 1 5/8" thick poplar wood (a great wood to use for laminating as it is bendable without steaming) and passed each one through a table saw about 25 times, cutting a 1/8" strip off the side each time. Since the wood was 1 5/8" thick, the thin strips, and the eventual curves of the table, ended up being 1 5/8" wide.
The second step in laminating wood is to put wood glue on both sides of each strip of wood and then to stack the strips until they reach the thickness you want your curve to have. In the final step, the stacked pieces of wood are bent together into the desired shape and clamped there. Once the glue sets and the clamps are removed, the wood will hold its shape.
The first hurdle I faced was figuring out how to make all four wooden pieces identical. I planned on laminating each one, but I couldn't use the same process that I employed for the prototype. With the prototype, I didn't pay much attention to making each piece identical; if there were a few irregularities, it really didn't matter. As shown in the picture above, I free-formed each curve between two cinder blocks and then clamped them in place. But the second time around, as I hoped to turn the design into a functional coffee table, I had to make sure that each piece was exactly the same. Any irregularities may cause the tabletop to sit unevenly on the stand or to wobble. The solution I came up with was to make a mold that would serves as a guide in laminating each curve. I designed the mold on a computer and used a CNC machine to cut it out. Once I had that, I was able to clamp glued stacks of the thin strips of poplar into the mold and let them dry there.
After allowing each piece to dry, I useda belt sander and palm sander to clean all the bits of dried glue from each curve- a very monotonous and time-consuming process. Next I used a drill press to drill out the areas where the steal cable would be passing through. Once done with that, I threw a little polyurethane on and voila!
Now it was time to assemble the four pieces into the table stand. For this step, I used a method that I developed my senior year in college and that I have been using in many of my projects since. The concept is to string steel cables between opposing curves in such a way so that there are some cables providing a tension that pulls the curves together and other cables providing tension that pulls the curves apart. In the end, you have two counteracting but equal forces, with the result being that the curves do not move at all in relation to one another. Before wiring the curves together, though, I first had to make a jig the hold each piece in the right place.
Once the jig was set, I began passing the cables through their corresponding holes and locking them in place by crimping copper sleeves around them.
This method of wiring provides a great deal of stability despite the fact that, in the end, none of the wooden pieces actually touch one another and each one only contacts the ground in one place.
Once the final cable was secured in place, all that was left to do was trim a few cables, remove the stand from the jig and put some glass on top! I'm really happy with the final product. I may have said this before, but I think this is my favorite table yet!